Carefuly open the box. sometimes, rarely, but sometimes, the cham has gotten loose in the box and you dont want to cut them with the knife or let them escape.
once the box is opened, you can carefully remove the cup or bag the cham is in.
remove the lid, and if you cham is willing, you can let them crawl on your hand so you can place them in the cage.
If they wont come out of the cup, just leave the lid off, and place the cup with them in it in the cage, positioned so the cham can grab something to get out of the cup.
I would spray the leaves of your cage down first, getting them nice and wet, before you place your cham in the cage, so that they can drink. shipped chams are often dehydrated.
then, let her be. dont touch her or watch her for a few hours, and it can take several days to even weeks for them to settle in,